A roller tappet intended for use a) in a high pressure fuel pump; b) in a valve train of an internal combustion engine; c) in an engine such as an axial piston engine or a radial piston engine; or d) generally for a pump/compressor of an axial piston type or of a radial piston type.
1. A roller tappet ( 1 ), comprising:
a housing ( 2 ) having:
an outer wall ( 4 );
a drive side front end ( 3 );
a driven side front end ( 10 );
two diametrically opposing flats ( 5 ) receding from the outer wall ( 4 ) proximate said drive side front end ( 3 ), each of said two flats ( 5 ) comprising a U-shaped reception ( 6 ) open in a direction towards the drive side front end ( 3 ), and framed by a respective window ( 18 );
a plurality of fingers ( 19 ) projecting inwards; and,
a pin ( 7 ) mounted in said receptions ( 6 ), the pin having:
a bearing means ( 9 );
a central section ( 13 ) of a large diameter; and,
two annular shoulders ( 14 ) of a small diameter;
a roller ( 8 ) serving as a run-on surface of a periodic stroke producer being mounted through the bearing means ( 9 ) on said pin ( 7 );
a support ( 25 ) for a tappet follower element being seated on the driven side front end ( 10 ) of the housing ( 2 ); and,
a retention means ( 11 ) being provided for the pin ( 7 ) in an axial direction of the pin ( 7 ) for preventing the pin ( 7 ) from exiting axially out of the housing ( 2 );
wherein the central section ( 13 ) of the pin ( 7 ) carries the roller ( 8 ) and extends to a point directly in front of an inner side ( 24 ) of the two diametrically opposing flats ( 5 ), and the retention means are formed by the fingers ( 19 ) projecting inward up to a point directly in front of a corresponding annular shoulder of the annular shoulders ( 14 ) from an upper transverse side ( 17 ) of the respective windows ( 18 ) of the housing ( 2 ).
2. The roller tappet as recited in claim 1 , wherein the receptions ( 6 ) have lateral sides ( 16 ) extending in an axial direction of the tappet ( 1 ), and are straight.
3. The roller tappet as recited in claim 1 , wherein two annular steps ( 15 ) are formed between the two annular shoulders ( 14 ) and the central section ( 13 ) of the pin ( 7 ), and the bearing means ( 9 ) of the roller ( 8 ) has ends that are flush with the annular steps ( 15 ) of the pin ( 7 ).
4. The roller tappet as recited in claim 1 , wherein the bearing means ( 9 ) comprises at least one needle roller bearing or sliding bearing or a combination of a needle roller bearing and a sliding bearing.
5. The roller tappet as recited in claim 1 , wherein the outer wall ( 4 ) of the housing ( 2 ) between the upper transverse sides ( 17 ) of the two windows ( 18 ) comprising the fingers ( 19 ) is configured as a closed continuous ring ( 21 ).
6. The roller tappet as recited in claim 1 , wherein the flats and the fingers are integral with the housing, and the housing ( 2 ) is made out of thin-walled sheet steel.
7. The roller tappet as recited in claim 1 , wherein the fingers ( 19 ) protrude as incised material integrally from the transverse sides ( 17 ) of the fingers ( 19 ) and are bent inwards into a tappet interior ( 20 ).
8. The roller tappet recited in claim 1 , wherein the roller tappet ( 1 ) is intended for use a) in a fuel pump; b) in a valve train of an internal combustion engine; c) in an engine such as an axial piston engine or a radial piston engine; or d) for a pump/compressor of an axial piston type or of a radial piston type.